My son very often works ridiculously long hours but I wouldn’t dream of rewarding him for it now that he’s married. He’s not my little boy any more and your son isn’t yours, he’s a married man. As V3ra said, his wife will have suffered from his absence. You should have treated both of them, not just him, if you absolutely had to make a thing of it. Hard work is a fact of life - he’s not a child who’s done well in his exams, but effectively that’s how you’ve treated him. I hope you learn from this and can repair the damage. Incidentally, you may get on extremely well with your daughter in law and that’s great, but she’s not your ‘long term bf’.